There has been conventionally proposed such a technology by which when an image processing apparatus receives a print instruction from outside, an apparatus other than the image processing apparatus, such as a server, executes a print process based on the print instruction. For example, there has been disclosed such a system, in which a printing device receives a print instruction from a user via a web browser. The printing device communicates with a print instruction receiving application server by designating text data, for which the print instruction was issued. The print instruction receiving application server converts the designated text data into print data. The printing device can receive another print instruction, while the print instruction receiving application server is generating the print data.